This invention relates to a device for continuous production by extrusion cooking of a co-extruded food product containing whole solid pieces, such as for instance peanuts, cashew nuts, almonds, hazelnuts, or any other whole dried fruit or seed.
The invention also relates to an extrusion machine provided with such a device.
Co-extruded composite food products are known which include an outer wrapping made of a cooked cereal-based paste, and a liquid, half-liquid or pasty inner filling inserted in the middle of the outer wrapping.
For producing such products, it is known to make use of an extrusion machine conventionally including at least one screw driven in rotation inside a body having an elongated shape and performing adequate processing on the starting material via a series of steps, such as for instance mixing, pressing, shearing, and/or cooking.
The downstream end of the cylinder of the extrusion machine is provided with a die through which the food product is discharged from said extrusion machine.
The inner filling of the outer extruded wrapping is in general inserted by means of a pump into the tubular die for forming this outer wrapping.
This liquid or pasty filling, which can still be pumped, must not include solid particles, or else they are limited to very small particles embedded within the liquid or paste.
Known devices do not allow for bringing into the die large size whole pieces in the solid state thereof while maintaining integrity of the shape thereof.
Indeed, going through a pump and an injection cannula if the pieces are inside the stuffing or in the screws of the extrusion machine and in the die if the pieces are in the paste will lead to deterioration and crushing of the pieces. Also, the pieces are arranged in a completely random distribution and not in regular intervals inside the paste or stuffing.